Hi Jaime,
It looks like the data you are plotting has a text column for the x-axis, rather then a true date column column. The Box command will order text, or categorical data, alphabetically by default on the x-axis, but you can change that. We made up some data to show a worked example.
Here the data is grouped according to the date in a text format. The x-axis is ordered alphabetically.
The values in the data table are ordered chronologically. So, the Labels menu can be set to the same column. Now the boxes are shown chronologically as well.
If you have the raw dates in a Date column you can also use these, and then you would have a true date axis.
Anyway, hope this helps. Let us know!
(sorry for the delay in responding, we are catching up from end of summer vacation)